Electronic devices containing semiconductors generate a significant amount of heat during operation. The level of heat generated is related to the performance of the semiconductor, with more highly performing devices generating greater levels of heat. In order to cool the semiconductors, which must be cooled in order to obtain appreciable performance, heat sinks are affixed to the device. In operation, heat generated during use is transferred from the semiconductor to the heat sink where the heat is harmlessly dissipated. In order to maximize the heat transfer from the semiconductor to the heat sink, a thermally conductive material, known as a thermal interface material (TIM), is utilized. The TIM ideally provides intimate contact between the heat sink and the semiconductor to facilitate the heat transfer.
There are various types of TIMs currently used by semiconductor manufacturers, all with their own advantages and disadvantages. For those semiconductors generating significantly high levels of heat, a preferred thermal solution is the use of solder materials. Examples of solder materials are pure indium, or alloys of indium and silver, or alloys of tin, silver, and copper, or alloys of indium, tin, and bismuth. These materials provide high thermal conductivity (30 to 50 W/m-K), but they are prone to cracking and delamination under stress.
Thus, it would be advantageous to provide a thermal interface material that is easy to handle and apply, yet also provides a high thermal conductivity and reliable performance.